From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B8B57C2BA2B for ; Thu, 16 Apr 2020 05:27:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9963E20936 for ; Thu, 16 Apr 2020 05:27:08 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="HUErtq3U" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2406621AbgDPF1G (ORCPT ); Thu, 16 Apr 2020 01:27:06 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37014 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S2406351AbgDPF0o (ORCPT ); Thu, 16 Apr 2020 01:26:44 -0400 Received: from mail-pl1-x642.google.com (mail-pl1-x642.google.com [IPv6:2607:f8b0:4864:20::642]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 216ABC061A0F for ; Wed, 15 Apr 2020 22:26:44 -0700 (PDT) Received: by mail-pl1-x642.google.com with SMTP id k18so949713pll.6 for ; Wed, 15 Apr 2020 22:26:44 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=oYx3rFG6KM20BdDmNDmRew1PF1Kw/jTeIMBMcMn6Uag=; b=HUErtq3UvZ5uwOow+WJX2AdXLUZNH3EYTmjk1UnWAicVd/8Oq4rS+5iZT/pPWIgopr 9vtmrNOLGfSrNontxw2/IvOKbuFu7qJJfOp4VFegTfW17BiCSbbuFDoxOZhIezEuq7ft w1VYv0JrqmzhoTrE4ru74gTH76FFMWJCCXRPIenWlCbIVXKKjC9m82YAZ2Xd1g0aVlSw LcpbVAKIdnCq23MpjjQGF3uHQqJDX1ebFQC6m06JL7NDw1aXI34fUprRI4+mhYHq6H+D GzDf7ykQ9EKJ7NkvyTfird2NPNLRVH6h6KmXbhygnHQ669kjabD1gkP7f/5QmNMgnrP5 zWzw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=oYx3rFG6KM20BdDmNDmRew1PF1Kw/jTeIMBMcMn6Uag=; b=hDN/jdzntspRfXl5JJs0p9bzhoDga+Dbr/KUZZwsRJB5G6AzwtAfPtjfP3j1+EHlcf NzVMcoP6VJW/Re3Pr5GnCX8Nsal4RKJzJE08ihIUiBGHrf4kRdAPMjFgRTW2m2JNErqD PHlKBGkBB8yYWtoQ6V9/NlZZ1iiibMv+1MueT7xALpL+JiZY+QE5KtKgs3ABRtUTmzDs GbhIxmbPwhG3ggOWgX418Y3d3LJK/DYvZqexwAjmZeR9Yyy+pcml+wAWBdWyp7CgFcZG DsZN+/U+3wyIob8EWteB3QBOPY/d+hv1Zl53u54jT+nuNNMQGHQHFmdJlSYVprEb+d7V Ayng== X-Gm-Message-State: AGi0PuZZwgSJuWUp94aefKbavfSBNb1oI8oFotQVknwAsRxspqKe9lsp ax8dKttiF1PzuUCylxDjCcQ= X-Google-Smtp-Source: APiQypK/2FwQOgHFn/PlAUl6famODzCE4lTGQ6yxpTUvumbVbDZFXkExYLzU004YRAurasnvaR75mg== X-Received: by 2002:a17:90a:cc2:: with SMTP id 2mr3160651pjt.33.1587014803490; Wed, 15 Apr 2020 22:26:43 -0700 (PDT) Received: from laptop.hsd1.wa.comcast.net ([2601:600:817f:a132:df3e:521d:99d5:710d]) by smtp.gmail.com with ESMTPSA id c21sm53699pjr.2.2020.04.15.22.26.42 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 15 Apr 2020 22:26:43 -0700 (PDT) From: Andrei Vagin To: Vincenzo Frascino , Catalin Marinas , Will Deacon Cc: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Mark Rutland , Thomas Gleixner , Andrei Vagin , Dmitry Safonov Subject: [PATCH 1/6] arm64/vdso: use the fault callback to map vvar pages Date: Wed, 15 Apr 2020 22:26:13 -0700 Message-Id: <20200416052618.804515-2-avagin@gmail.com> X-Mailer: git-send-email 2.17.2 In-Reply-To: <20200416052618.804515-1-avagin@gmail.com> References: <20200416052618.804515-1-avagin@gmail.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This is required to support time namespaces where a time namespace data page is different for each namespace. Reviewed-by: Vincenzo Frascino Signed-off-by: Andrei Vagin --- arch/arm64/kernel/vdso.c | 24 +++++++++++++++--------- 1 file changed, 15 insertions(+), 9 deletions(-) diff --git a/arch/arm64/kernel/vdso.c b/arch/arm64/kernel/vdso.c index 354b11e27c07..290c36d74e03 100644 --- a/arch/arm64/kernel/vdso.c +++ b/arch/arm64/kernel/vdso.c @@ -114,28 +114,32 @@ static int __vdso_init(enum arch_vdso_type arch_index) PAGE_SHIFT; /* Allocate the vDSO pagelist, plus a page for the data. */ - vdso_pagelist = kcalloc(vdso_lookup[arch_index].vdso_pages + 1, + vdso_pagelist = kcalloc(vdso_lookup[arch_index].vdso_pages, sizeof(struct page *), GFP_KERNEL); if (vdso_pagelist == NULL) return -ENOMEM; - /* Grab the vDSO data page. */ - vdso_pagelist[0] = phys_to_page(__pa_symbol(vdso_data)); - - /* Grab the vDSO code pages. */ pfn = sym_to_pfn(vdso_lookup[arch_index].vdso_code_start); for (i = 0; i < vdso_lookup[arch_index].vdso_pages; i++) - vdso_pagelist[i + 1] = pfn_to_page(pfn + i); + vdso_pagelist[i] = pfn_to_page(pfn + i); - vdso_lookup[arch_index].dm->pages = &vdso_pagelist[0]; - vdso_lookup[arch_index].cm->pages = &vdso_pagelist[1]; + vdso_lookup[arch_index].cm->pages = vdso_pagelist; return 0; } +static vm_fault_t vvar_fault(const struct vm_special_mapping *sm, + struct vm_area_struct *vma, struct vm_fault *vmf) +{ + if (vmf->pgoff == 0) + return vmf_insert_pfn(vma, vmf->address, + sym_to_pfn(vdso_data)); + return VM_FAULT_SIGBUS; +} + static int __setup_additional_pages(enum arch_vdso_type arch_index, struct mm_struct *mm, struct linux_binprm *bprm, @@ -155,7 +159,7 @@ static int __setup_additional_pages(enum arch_vdso_type arch_index, } ret = _install_special_mapping(mm, vdso_base, PAGE_SIZE, - VM_READ|VM_MAYREAD, + VM_READ|VM_MAYREAD|VM_PFNMAP, vdso_lookup[arch_index].dm); if (IS_ERR(ret)) goto up_fail; @@ -215,6 +219,7 @@ static struct vm_special_mapping aarch32_vdso_spec[C_PAGES] = { #ifdef CONFIG_COMPAT_VDSO { .name = "[vvar]", + .fault = vvar_fault, }, { .name = "[vdso]", @@ -396,6 +401,7 @@ static int vdso_mremap(const struct vm_special_mapping *sm, static struct vm_special_mapping vdso_spec[A_PAGES] __ro_after_init = { { .name = "[vvar]", + .fault = vvar_fault, }, { .name = "[vdso]", -- 2.24.1